The present invention relates to methods and apparatus for recommending television programming, and more particularly, to techniques for evaluating television program recommenders.
As the number of channels available to television viewers has increased, along with the diversity of the programming content available on such channels, it has become increasingly challenging for television viewers to identify television programs of interest. Historically, television viewers identified television programs of interest by analyzing printed television program guides. Typically, such printed television program guides contained grids listing the available television programs by time and date, channel and title. As the number of television programs has increased, it has become increasingly difficult to effectively identify desirable television programs using such printed guides.
More recently, television program guides have become available in an electronic format, often referred to as electronic program guides (EPGs). Like printed television program guides, EPGs contain grids listing the available television programs by time and date, channel and title. Some EPGs, however, allow television viewers to sort or search the available television programs in accordance with personalized preferences. In addition, EPGs allow for on-screen presentation of the available television programs.
While EPGs allow viewers to identify desirable programs more efficiently than conventional printed guides, they suffer from a number of limitations, which if overcome, could further enhance the ability of viewers to identify desirable programs. For example, many viewers have a particular preference towards, or bias against, certain categories of programming, such as action-based programs or sports programming. Thus, the viewer preferences can be applied to the EPG to obtain a set of recommended programs that may be of interest to a particular viewer.
Thus, a number of tools have been proposed or suggested for recommending television programming. The Tivo(trademark) system, for example, commercially available from Tivo, Inc., of Sunnyvale, Calif., allows viewers to rate shows using a xe2x80x9cThumbs Up and Thumbs Downxe2x80x9d feature and thereby indicate programs that the viewer likes and dislikes, respectively. Thereafter, the TiVo receiver matches the recorded viewer preferences with received program data, such as an EPG, to make recommendations tailored to each viewer.
There is currently no way, however, to validate the recommendations generated by such tools for recommending television programming, short of testing the tools with human volunteers. In addition, there is no way to determine when the recommendations have achieved a given level of accuracy. A need therefore exists for a method and apparatus for validating recommendations generated by a television program recommender. A further need exists for a method and apparatus for determining when the size of the viewing history (record of shows watched/not watched) is sufficient to provide a given level of accuracy.
Generally, a method and apparatus are disclosed for evaluating the effectiveness of a television program recommender by evaluating program recommendations generated by the television program recommender for one or more programmed viewing agents. A viewing agent is programmed with a set of rules that characterize the viewing preferences of a modeled viewer. Viewing agents of varying complexity and having varying program preferences can be constructed by defining various rules that characterize program attributes, such as genre, actors and program duration.
During a training phase of the present invention, a viewing agent containing the programmed rules is applied to a set of training programs from an electronic program guide (EPG) to algorithmically obtain an agent viewing history, indicating whether the viewing agent would have liked or disliked each training program. The generated agent viewing history is then processed by the profiler portion of the television program recommender being evaluated. The profiler derives an agent profile containing a set of inferred rules that attempt to mimic the programmed preferences of the viewing agent. Thus, the profiler attempts to derive the viewing habits of the viewing agent based on the set of programs that the viewing agent liked or disliked.
During an evaluation phase of the present invention, the programmed rules of the viewing agent are applied to test data from an electronic program guide (EPG) to obtain an agent evaluation viewing set. In parallel, the television program recommender generates a set of program recommendations by applying the agent profile generated during the training phase to the test data from the electronic program guide (EPG). The present invention can then compare the agent evaluation viewing set (generated from the programmed rules) with a set of program recommendations produced by the television program recommender being evaluated (generated from the inferred rules). In this manner, the effectiveness of the television program recommender can be evaluated.
According to another aspect of the invention, a method and apparatus are disclosed for determining the required size of the viewing history to provide a given level of accuracy. Generally, the size of the required viewing history can be obtained by utilizing viewing histories of varying sizes for the same viewing agent. Thereafter, the size of the viewing history required to exceed a predefined accuracy threshold can be obtained.
The viewing agents can be programmed to introduce one or more random shows into the viewing history, allowing the television program recommender validator to determine how the program recommender processes such noise. In a further variation, the viewing agents can be programmed to gradually change the programmed viewer preferences over time, allowing the television program recommender validator to determine how the program recommender responds to such changes.
A more complete understanding of the present invention, as well as further features and advantages of the present invention, will be obtained by reference to the following detailed description and drawings.